This invention pertains to an adapter for mounting cable connectors. More particularly, this invention pertains to a fiber optic mounting adapter which is positioned a control box or other mounting structure to facilitate the connection of two fiber optic cables.
Many forms of communication transmission and power transmission require physical lines that connect a source terminal to a destination terminal. These physical lines are generally buried in the ground or placed above ground level. In many situations, there is no easy way to access or repair the physical line in the event that the physical line is damaged.
In some applications, such as fiber optics, a stable connection needs to be maintained between terminals. This connection requires that the terminals be properly aligned and held steady during operation in a clean connection. These connections are susceptible to damage caused by sudden motion. Sudden motion may damage the physical line by pulling, tearing, or breaking the physical line.
Physical cables may be used to transmit both power and information. These physical cables are generally made up of a plurality of segments connected together through junctions. In many applications, such as fiber optics, at junctions where a first terminal is connected to a second terminal, a rigid connection is required. The advantage of a rigid connection is that it promotes the connection between the first terminal and the second terminal with transmission mediums such as light waves, electrical signals, or power. The disadvantage of such a connection is that any force applied to the connection may result in damage to the physical cable connected by the junction. In order to avoid damage caused by forces applied to the junction, a quick release mechanism is available to provide the advantages of a physical connection between the first and second terminal while allowing for a quick release of the first terminal from the second terminal in the event of a force being applied to the junction.
For both outdoor and in-building installation of fiber optic and other communication cables, such cables are often placed in conduit or other ducts. The conduit provides protection for both physical and environmental abuse. In underground installations, the conduit protects the cable from shifting rocks, aggressive rodents, digging equipment, and other hazards. Because fiber optic cables have a lower breaking strength and are more easily damaged than copper cables, the use of conduits offers needed protection for fiber optic cables. In metropolitan areas, multiple conduits are often grouped as duct banks to accommodate future growth of the cable infrastructure without major traffic disruptions from cutting and trenching of the streets.
There are a number of applications in the area of traffic monitoring and control, as well as road structure monitoring, where communicating information to a traffic management center or other control center via a fiber optic communication system is advantageous. For the traffic and road monitoring applications, control boxes are generally mounted along the edge of the highway or local streets in proximity to the location where information is being collected. One of the most expensive problems in operating such fiber optic systems is to repair damages caused by traffic accidents which physically damage the control boxes. The fiber optic connections inside the control boxes are often ripped apart and destroyed, and the fiber optic line may be dragged from a first location to a second location by a vehicle. In such a case, the line may need to be re-laid from the source to the destination. The process of replacing fiber optic connectors and relaying fiber optic cable is time consuming, labor intensive, and expensive. In order to avoid the damage caused by sudden motion to a physical line, quick-release fiber optic cable connectors may be used. There is also a need for an adapter to facilitate the mounting and servicing of the fiber optic connectors in a control box.
A typical fiber optic cable includes a fiber optic connector at each end. An optical connector consists of a ferrule, through which the optical fiber is fed. The distal end of the ferrule and fiber combination is polished to a precise endface geometry. The ferrule and fiber endface is butted to another fiber optic cable's ferrule and fiber endface, bringing the fiber endfaces into precise physical contact. In order to minimize signal loss, the fiber and ferrule endfaces must have a very smooth and clean surface. Cleanliness of the fiber and ferrule endface is critical to the good performance of fiber optic connectors. In particular, any imperfections or small particles of dirt on the ends of the optical fibers will tend to reduce the amount of the light energy that passes from one cable to the other. As the amount of imperfections (e.g., scratches) and dirt increases at the optical fiber ends, less and less light energy passes from one cable to the other. In extreme situations, the amount of light energy loss is so great that light detection circuitry at the end of the fiber optic pathway is no longer able to detect the light signal.
For connecting fiber optic cables in an indoor room with controlled access, various mounting racks and other mounting devices may be used facilitate the fiber optic connections. But in the outdoor control boxes and other severe environments, the connectors and the mounting adapters must be more rugged, with features to facilitate the installation, maintenance, and repair of the fiber optic cables and connectors in such environments.